The role of brain catecholamines (CAs) in mental function has been the subject of intensive investigation for some time. Much attention has been given to the mechanisms of action of psychotomimetic CNS stimulants (amphetamine, cocaine, methylphenidate) because they can produce hallucinations and paranoid ideation, and exacerbate schizophrenic symptoms. Amphetamine has been the most extensively studied CNS stimulant, and it seems to release newly synthesized CA, dopamine (DA) and/or norepinephrine (NE), and inhibit their re-uptake. The potent non-amphetamine stimulant, amfonelic acid (AFA), produces similar behavioral effects in animals and man to that of amphetamine, however, its effects are not blocked by CA synthesis inhibition but by CA depletion (reserpine). Furthermore, AFA and amphetamine have strikingly different effects on the DA neuron, while preliminary studies suggest that AFA, unlike amphetamine, does not effect the NE neuron. The goal of the proposed research is to investigate the effects and differential modes of action of amphetamine and AFA on (1) DA and NE central metabolism and turnover, (2) impulse flow in central DA and NE neuronal systems, and (3) a behavioral model utilizing intracranial self-stimulation with electrodes in DA and NE brain regions. This tripartite investigtion is designed to allow a balanced research effort calculated to allow the most complete interpretation possible of the research results on the roles of DA and NE in mental function and dysfunction.